Tool holder

ABSTRACT

A shaving tool holder for use on automatic screw machines or the like. The tool holder is self-adjusting and carries a roller for engaging the work at a location opposite the tool. The roller and tool are supported on a head positioned at one end of a pivoted arm. The arm is spring biased to permit the tool and roller to align with the work.

United States Patent Inventor Lewis Bernath [56] References Cited A l NMich. UNITED STATES PATENTS pp o. Filed Apt 1, 1969 1,751,078 3/1930Drowns 82/35 Patented Apr. 27, 1971 Primary Examiner-Francis S. HusarAssignee Federal Screw Works Attorney-Harness, Dickey and PierceDetroit, Mich.

ABSTRACT: A shaving tool holder for use on automatic g g screw machinesor the like. The tool holder is self-adjusting alms rawmg and carries aroller for engaging the work at a location US. Cl 82/35 opposite thetool. The roller and tool are supported on a head lnt. Cl B23b 29/16positioned at one end of a pivoted arm. The arm is spring Field ofSearch 82/35 biased to permit the tool and roller to align with thework.

17 37 14/ i;t.- I} W if PATENTED APR27 I97] sum 3 or a INVENTOR.

root rroimza SUMMARY OF THE INVENTION The tool holder of the presentinvention is characterized by the use of a pivoting arm which carries ahead at one end thereof. The arm is pivotable within a guiding slot, oneside of which is defined by a gib which may be adjustable to compensatefor wear. The tool and a backup roller are carried on a head fastened toone end of the arm. The angular position of the head on the arm is veryaccurately controlled by set screws which define stops or abutments forthe head. The tool holder possesses great flexibility in usage, the armand head being reversible for utilization at different stations on anautomatic screw machine. The support on which the arm is pivoted isclamped in a selected position along a guideway of a base. By thismeans, the position of the tool laterally of the work can be changedwithout disturbing the squareness of the tool relative to the work. Thetool holder of the present invention possesses a degree of accuracy farsurpassing other commercially available tool holders and has been foundto be highly dependable. The overall construction is one of extremeruggedness combined with great precision.

DESCRIPTION OF THE VIEWS OF THE PREFERRED EMBODIMENTS FIG. 1 is aside-elevational view of a tool holder made in accordance with thepresent invention.

FIGS. 2 and 3 are plan and end elevational views, respectively, of thestructure illustrated in FIG. 1;

FIG. 4 is a sectional view of the structure illustrated in FIG. 2, takenon the line 4-4 thereof;

FIG. 5 is a sectional view of the structure illustrated in FIG. 4, takenon the line 5-5 thereof;

FIG. 6 is a sectional view of the structure illustrated in FIG. 5, takenalong the line 6-6 thereof;

FIG. 7 is a sectional view of the structure illustrated in FIG. 4, takenalong the line 7-7 thereof; and

FIG. 8 is a view of the structure similarly illustrated in FIG. 4,showing a modified form of the invention.

Referring now to the drawings, the tool holder includes a base 11 whichis designed to be rigidly secured in a selected position on a slide (notshown) of an automatic screw machine, or the like. An abutment strip 13is utilized in positioning the base 11 on such slide. The base 11 has apair of spaced parallel upstanding sidewalls 15. The walls 15 have keysor guideways 17 formed at the upper ends thereof. A support member 19 ispositioned between the walls 15 and projects upwardly therefrom. Thesupport member 19 has a cross-sectional shape similar to an inverted Uand is provided with longitudinally extending keyways 21 in which thekeys 17 are conformably fitted to support the member 19 for slidingmovement. The keyways 21 are formed in the outer sides of spacedparallel sidewalls 23 connected by an upper wall 24. A pair of screws 25are threaded into each of the walls 23 and project through elongatedslots 27 formed in the walls 15 of the base 11. The screws 25 carrywashers 29 and upon the tightening of the screws the sidewalls 15 areclamped between the washers 29 and the walls 23 of the support member19. By this means the support member 19 may be locked in variousselected positions longitudinally of the base 11.

A lever arm 31 is supported for pivotal movement between the walls 23 ona pivot pin 33. The pivot pin 33 is supported between the walls 23 atthe rear end thereof. The arm 31 extends longitudinally between thewalls 23 and projects from the support member 19 at the forward endthereof. The vertical pivoting movement of the forward end of the arm 31is guided between a wall 35 formed on the inside of one of the walls 23and a wall 37 fonned on one side of an adjustable gib 39. The spacingbetween the walls 35 and 37 is controlled by screws 41 threaded throughone of the walls 23 and bearing against the gib 39. Accordingly, lateralwobble or displacement of the forward end of the arm 31 is restrained.It should be noted, however, that the walls 35 and 37 do not clamp thearm 31, but permit it to move vertically therebetween.

The arm 31 is biased downwardly by a coil spring 43 which is seatedagainst a plug 45. The plug 43 is threaded into a generallysleeve-shaped guide member 47 which is, in turn, threaded into anopening 49 of the wall 24. By rotating the plug 45, it may be moved upand down within the guide member 47 and the position of the seat for thespring 43 varied. By this means the force which the spring 43 applies tothe am 31 can be regulated. The position to which the arm 31 is biasedby the spring 43 is determined by means including a stud 51 threadedinto an opening 53 in the arm 31 at a location between the spring 43 andthe pivot pin 33. The stud 51 passes freely through a larger diameteropening 55 formed in the wall 24 and receives a pair of nuts 57 whichbear against a washer 59. The washer 59 abuts the upper surface of thewall 24 to limit downward movement of the forward end of the arm 31under the force of the spring 43. Accordingly, the stud 51 and thestructure it carries, the arm 31., and the wall 24 may be said toprovide interengaging stop" or "abutment" means.

The arm 31 is provided with an opening 61 extending longitudinallythrough the entire length thereof. A bolt 63 extends through saidopening with its head 65 bearing against the rear end of the arm 31. Theforward end of the bolt 63 is threaded into a tapped hole 66 formed] ina head 67. The head 67 serves to support a shaving tool 69 and a backuproller 71. The arm 31 has a forwardly projecting shoulder portion 73which is positioned within a larger sized recess 75 in the rear side ofthe head 67. The bolt 63 holds a flat surface 76 on the rear of the headagainst a flat surface 77 formed on the forward end of the arm 31. Inorder to prevent the head from pivoting about the bolt axis a pair ofset screws 79 are threaded through the head 67 so as to project into therecess 75 and engage the shoulder portion 73 on opposite sides thereof.By advancing one of the set screws 79 and retracting the other of saidset screws, the angular position of the head 67 about the axis of thebolt 63 can be very accurately controlled and the head can be preventedfrom turning.

The backup roller 71 is rotatably supported on a bracket 81 which issecured on the head 67 for adjustment toward and away from the tool 69.The backup roller 71 is adapted to engage a workpiece W on thediametrically opposite side thereof from the tool 69. Likewise, the tool69 may be adjustably clamped in a selected position on the head 67. Theparticular manner in which the backup roller 71 and the tool 69 arepositioned on the head 67 forms no part of the present invention. Theusage of the tool is such that the entire tool holder is advanced in adirection parallel to the axis of the bolt 63, said direction beingherein referred to as one which is longitudinalof the tool holder. Thisis accomplished by the movement of a slide (not shown) of the automaticscrew machine, or the like, on which the toolholder is mounted. Theworkpiece W is, of course, driven in rotation. Should there be somemisalignment between the tool 69 and the workpiece W, any suchmisalignment is overcome by setting up the tool holder in such a mannerthat the backup roller 71 will first contact the workpiece W, assuringthat: the tool 69 will take a bite into the work of the desired depth.If desired, the force applied by the spring 43 may be made so strongthat little or no deflection of the arm 31 against the spring willoccur.

One of the particularly desirable features of the tool holder is theability to reverse of invert the head 67 and arm 31. This is donerelatively simply by knocking out the pivot pin 33, removing the arm 31and head 67 from the support 19, rotating this assembly 180 andreinserting the pivot pin 33 in another hole 83 of the arm 31. Thisproduces the arrangement of parts illustrated in FIG. 8. In thisarrangement of parts, a hole 85 in which the pivot pin 33 was previouslypositioned is empty. For the arrangement shown in FIG. 8 the stud 51,together with its associated structure, is removed and set aside, as arethe coil spring 43, guide member 47, and plug 45. In their place anabutment stud 86 is threaded into the opening 55 and is secured in placeby a locknut 87. Similarly,

a threaded stud 89 is threaded into a tapped hole 91 of the arm 31 andpasses upwardly freely through a washer 93, which is seated on thesupport member 19 over the upper end of the opening 49. The stud 89carries a pair of nuts 95 and a washer 97 at its upper end which bearagainst the upper end of a coil spring 99. By this arrangement an upwardbiasing force is applied to the arm 31, causing the arm to engage a stopdefined by the lower end of the stud 86. The arrangement of partsillustrated in FIG. 8 is necessary for the installation of the toolholder at certain stations of most automatic tool machines. Whether thearrangement illustrated in FIG. 4 or FIG. 8 is necessary will dependupon the direction of rotation to the workpiece W with respect to theside of the workpiece from which the tool holder is advanced toward theworkpiece. Tool holders used on one side of the workpiece W will requireone position of the parts and tool holders used on the other side willrequire another position of the parts.

I claim:

1. A tool holder for machining a rotationally driven workpiece includinga base having a pair of upstanding laterally spaced parallel sidewalls,a support member having a pair of laterally spaced parallel sidewallsand an upper wall connecting said support member sidewalls at the upperends thereof, an arm pivotally mounted between said support membersidewalls, a cutter head carried at one end of said arm, said supportmember sidewalls being disposed in side-byside relation with said basesidewalls and being guided by said base sidewalls for movement parallelthereto, clamping means connecting said base and support membersidewalls for locking said support member in selected positions on saidbase and means pivotally biasing said arm.

2. The structure set forth in claim 1 in which said clamping meansincludes screws threaded into said supporting member, said base havinglongitudinally elongated slots in the sidewalls thereof which receivesaid screws.

3. The structure set forth in claim 1 including a gib disposed betweensaid arm and one of said support member sidewalls and means foradjusting said gib against said arm.

4. The structure set forth in claim 2 including screw means for holdingsaid head on said arm and interengaging shoulder and adjustable abutmentmeans between said arm and said head spaced laterally from said screw,said abutment means being adjustable to vary the angular position ofsaid head about the threaded axis of said screw.

5. The structure set forth in claim 1 in which said biasing meanscomprises a spring carried by said upper wall.

6. The structure set forth in claim 1 including means defining a stopfor limiting pivotal movement of said arm in one direction, said meansbeing associated with said upper wall.

7. The structure set forth in claim 1 including a pair of pivot pinopenings extending through said arm and a pivot pin selectivelyengageable in one of said openings and supported at its opposite ends bysaid support member walls, said openings being disposed equidistantabove and below a horizontal plane intersecting the axis of rotation ofthe workpiece.

8. The structure set forth in claim 1 including interfitting key andkeyway means on said base and support member sidewalls.

1. A tool holder for machining a rotationally driven workpiece includinga base having a pair of upstanding laterally spaced parallel sidewalls,a support member having a pair of laterally spaced parallel sidewallsand an upper wall connecting said support member sidewalls at the upperends thereof, an arm pivotally mounted between said support membersidewalls, a cutter head carried at one end of said arm, said supportmember sidewalls being disposed in side-by-side relation with said basesidewalls and being guided by said base sidewalls for movement parallelthereto, clamping means connecting said base and support membersidewalls for locking said support member in selected positions on saidbase and means pivotally biasing said arm.
 2. The structure set forth inclaim 1 in which said clamping means includes screws threaded into saidsupporting member, said base having longitudinally elongated slots inthe sidewalls thereof which receive said screws.
 3. The structure setforth in claim 1 including a gib disposed between said arm and one ofsaid support member sidewalls and means for adjusting said gib againstsaid arm.
 4. The structure set forth in claim 2 including screw meansfor holding said head on said arm and interengaging shoulder andadjustable abutment means between said arm and said head spacedlaterally from said screw, said abutment means being adjustable to varythe angular position of said head about the threaded axis of said screw.5. The structure set forth in claim 1 in which said biasing meanscomprises a spring carried by said upper wall.
 6. The structure setforth in claim 1 including means defining a stop for limiting pivotalmovement of said arm in one direction, said means being associated withsaid upper wall.
 7. The structure set forth in claim 1 including a pairof pivot pin Openings extending through said arm and a pivot pinselectively engageable in one of said openings and supported at itsopposite ends by said support member walls, said openings being disposedequidistant above and below a horizontal plane intersecting the axis ofrotation of the workpiece.
 8. The structure set forth in claim 1including interfitting key and keyway means on said base and supportmember sidewalls.